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Alpha scattering and capture reactions in the A = 7 system at low energies

P. Mohr·H. Abele·R. Zwiebel·G. Staudt·H. Krauss·H. Oberhummer·A. Denker·J. W. Hammer·G. Wolf
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Abstract

Differential cross sections for $^3$He-$α$ scattering were measured in the energy range up to 3 MeV. These data together with other available experimental results for $^3$He $+ α$ and $^3$H $+ α$ scattering were analyzed in the framework of the optical model using double-folded potentials. The optical potentials obtained were used to calculate the astrophysical S-factors of the capture reactions $^3$He$(α,γ)^7$Be and $^3$H$(α,γ)^7$Li, and the branching ratios for the transitions into the two final $^7$Be and $^7$Li bound states, respectively. For $^3$He$(α,γ)^7$Be excellent agreement between calculated and experimental data is obtained. For $^3$H$(α,γ)^7$Li a $S(0)$ value has been found which is a factor of about 1.5 larger than the adopted value. For both capture reactions a similar branching ratio of $R = σ(γ_1)/σ(γ_0) \approx 0.43$ has been obtained.

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P. Mohr, H. Abele, R. Zwiebel, G. Staudt, H. Krauss, H. Oberhummer, A. Denker, J. W. Hammer, G. Wolf. 1993-06-07. Alpha scattering and capture reactions in the A = 7 system at low energies. https://doi.org/10.1103/physrevc.48.1420

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